Crashes on win 10 maximise window with Opus 12.19.4 beta 64bit.
Did that only just start happening after installing the .4 beta?
We don't have any similar reports so far, for what it's worth.
Are any crash logs created when the problem happens? If there are some and you could send them to us, we might be able to see what's going wrong from there. Here's how to find them and what to do: